/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.runners.core;



import com.bff.gaia.unified.sdk.annotations.Experimental;

import com.bff.gaia.unified.sdk.annotations.Experimental.Kind;

import com.bff.gaia.unified.sdk.state.State;



/**

 * Interface for accessing a {@link StateTag} in the current context.

 *

 * <p>For internal use only.

 */

@Experimental(Kind.STATE)

public interface StateAccessor<K> {

  /**

   * Access the storage for the given {@code address} in the current window.

   *

   * <p>Never accounts for merged windows. When windows are merged, any state accessed via this

   * method must be eagerly combined and written into the result window.

   */

  <StateT extends State> StateT access(StateTag<StateT> address);

}